Over the past decade, cases of head lice have been increasing rapidly throughout the world, with an estimated ten million cases per year in the U.S. alone. Head lice, Pediculus capitis, are a major irritant to children and their parents. P. capitis have three life stages, including an egg stage, three juvenile instars, and an adult stage. Head lice infestations cause children to miss an estimated 12-24 million days of school per year. Ridding a person of head lice is an extremely difficult and frustrating task. Indeed, some families, particularly in developing countries, have chronic infestations that are never eradicated. Head lice and body lice, P. humanus, are extremely similar genetically, and recent research suggests that they may be members of the same species. The similarity of head lice to body lice is cause for concern because body lice vector several human diseases, including epidemic typhus and relapsing fever, diseases that killed many millions of people during the 20th century.
Several methods of treatment for head lice infestations are currently available, including pesticidal shampoos, specialized louse combs and home remedies. Many of these treatments may be inefficient in eliminating head lice infestations. For example, specialized shampoos have never been shown to effectively kill eggs, and hatched lice have begun to evolve resistance to most of them. The use of a louse comb to comb the hatched lice and eggs out of an individuals hair can be effective, but is very time intensive and tedious to use. Most parents do not have the patience to eliminate the infestation in this manner. Additionally, hot air treatments have been suggested as a possible treatment for lice. However, though hot air has been shown to kill lice and their eggs in vitro, such treatments are generally ineffective in vivo.
A method of eradicating head lice infestations is needed that effectively kills both hatched lice and their eggs, but is safe, reliable, and easy to use. Additionally, it would be desirable that such a method utilize non-chemical means to prevent the lice from developing resistances to the treatment and avoid any undesirable side effects to the patient.